Sole for a boot



FIG. 1 is a bottom front right perspective view of a sole for a boot showing my new design;

FIG. 2 is a bottom plan view; and

FIG. 3 is a right side elevational view, the left side being a mirror image.

The broken line showing of a boot upper in FIGS. 1 and 3 is for illustrative purposes only and forms no part of the claimed design. 

The ornamental design for a sole for a boot, as shown and described. 